Fuse-block or cut-out.



2 SHEETS-SHEET 1.

PATENTED OCT. 3l, 1905.

H. W. LAWRENCE. FUSE BLOCK 0R. GUT-OUT.

APrLIoATxoN FILED APR. so, 1904.

Mww

PATENTED OCT. 3l, 1905.

H. W. LAWRENCE. FUSE BLOCK 0R CUT-OUT.

2. T ...n E H n n S T \C v m E Y E H s na APPLICATION FILED APR.80,1904.

NTTED STATES PATENT oEEioE.

HARRY W. LAWRENCE, OF DENVER, COLORADO, ASSIGNOR TO THE NEW ENGLANDELECTRIC COMPANY, OF DENVER, COLORADO, A CORPORA- TION OF COLORADO.

FUSE-BLOCK OR CUT-OUT.

Specification of Letters Patent.

Patented Oct. 31, 1905.

T0 @ZZ whom it may concern:

Beitknown that I, HARRY W. LAWRENCE, a citizen of the United States ofAmerica, residing in the city and county of Denver, State of Colorado,have invented certain new and useful Improvements in Fuse-Blocks or Cut-Outs; and I do declare the following to be a full, clear, and exactdescription of the invention, such as will enable others skilled in theart to which it appertains to make and use the same', reference beinghad to the accompanying drawings, and to the figures of reference markedthereon, which form a part of this specilication.

My invention relates to improvements in fuse-blocks or cut-outs employedin the electric wiring of private houses, oflice-buildings, 850.; andthe objects of my invention are, iirst, to provide a fuse-block adaptedto receive the ordinary inclosed cartridge-fuse and also to completelyincase the same and which is so constructed as to facilitate the removalor replacement of the fuse or fuses; second, to provide a fuse-block towhich the circuitwires are connected in such a manner that accidentalshort-circuiting, due to the contact of any conducting material with theuninsulated ends of the live Wires, is positively prevented; third, toprovide a fuse-block and cover so constructed that should the coverthereof be left off for any purpose nothing could be laid against orhung across or dropped into the block or accidentally work into theblock in such a manner as to shortcircuit the poles or arrange itselfparallel with the inclosed fuses, so as to conduct the currentindependent of the fuse from one terminal to the other; fourth, toprovide a fuseblock that is adapted to operatively receive any of theinclosed fuses in usesuch as the knife-blade or screw-clamp orspring-clip inclosed fuses-and, fifth, to provide a fuseblock that isconstructed to prevent the spring-clamps that hold the inclosed fusesfrom being sprung back far enough to prevent their resilient return tooperative position. I attain these objects by the mechanism illustratedin the accompanying drawings, in which- Figure 1 is a plan View of myimproved fuse or cut-out block supplied with the fuses, clamps, andterminals to which the circuitwires are secured, the cover of the blockbeing removed. Fig. 2 is a longitudinal vertical sectional view on theline 2 2 of Fig. 1, the cover being shown thereon. Fig. 3 is atransverse sectional view on the line 3 3 of Fig. 2. Fig. 4 is atransverse sectional View on the line 4 4 of Fig. 2. Fig. 5 is a centrallongitudinal vertical sectional View through the block and cover. Fig. 6is a vertical longitudinal sectional view similar to Fig. 2, butomitting the cover, fuse, and clamp; and Fig. 7 is a perspective view ofthe block, the cover being shown raised above the block.

Referring tothe drawings, the numeral 1 indicates the block, which ispreferably constructed of vitrified porcelain, this material beingcapable of withstanding a very high degree of heat, and 2 the cover,which is of the same or of other suitable material. The block isprovided with two longitudinal chambers 3, Which are closed at each endby walls of suitable thickness and separated by a partition 4, whichwith the sides of the box form the side walls of the chambers 3.Apertures 5 extend through the end walls of each chamber on a level withthe floor of the chambers, and terminals 6 are secured in suitablerecesses 7 in the floor of the chambers and at the ends thereof. Theseterminals are such as are in general use and comprise plates 8 and 9 andfuse-clamps 10. The plates 8 are secured within the recesses 7 by screws11, which extend up through the bottom of the block, the heads of whichlie in recesses 12 in the bottom of the block, which recesses are filledwith a suitable cement to prevent the screws coming in Contact with anyconducting material. Upon the ends of the plates 8, adjacent to the endsof the chambers, are secured the plates 9 by screws 13, and betweenthese plates, which are slightly recessed for the purpose, are clampedthe ends of the circuitwires 14 and 15, as will be seen by reference toFig. 3. To the opposite ends of the plate 8 are riveted thespring-clamps 10, which hold the ends of the cartridge-fuses 10A, andthe terminals in each chamber are in alinement with each other and withthe apertures 5 in the ends of the chambers. The width of each chamberis such as to prevent the members of the fuse-clamps from being sprungapart more than is necessary in removing and replacing the fuses, thusobviating the possibility of accidentally springing the clamps IOObeyond the limit of their normal resilient tension, which, if it couldbe done, would ruin the contact of the clips around the terminals of thecartridge fuse and perhaps cause an arc, which mig'ht ruin the cut-outor at least would permit the fuse to drop out, and thereby break thecircuit. These fuses are of the type in general use, and thereforerequire no description. 1n order that the fuses may be easily andconveniently removed or replaced, I form semicircular recesses 16 in thesides of the block and centrally of the length thereof, which extendfrom the top of the block to the iioor of the chambers, and acorresponding recess 17 is also formed in the partition 4. Theserecesses 16 and 17 permit the thumb and forelringer to be passed aroundthe fuse, so that it may be easily grasped and withdrawn. The depth ofthe chambers 3 is such that when the fuses are clamped in positiontherein they and the cut-out terminals will be a suijcient distancebelow the top of the block to prevent their contact with any articlethat might inadvertently be placed across the face of the block andwhich otherwise would short-circuit the current. As before stated, thechambers are only a little wider than the width ot' the fuse-clamps inorder that the clamps may be sprung apart sufiiciently to insert orwithdraw the fuses, and in order to obviate the possibility or'articles, such as screws or nails or pieces of wire, from beingaccidentally dropped into the block in such a manner as to connect withthe two terminals of each fuse, which would shunt a portion ofthecurrent from the fuse and would prevent the fuse from blowing in case anexcess of current should pass over the circuit-wires and also to preventany possibility of such articles being laid or falling across theterminal ends of the two inclosed fuses, and thus short-circuiting theirpoles. The side walls of the chambers 3 are formed with projections 18,arranged in oppositely-positioned pairs on each side of the centralportion of the fuses or of the linger-recesses 16 and 17. Theseprojections extend from the bottom to the top of the chambers and towithin a very slight distance of each fuse, making it practicallyimpossible for anything to drop into the block in such a way as to makea circuit with the terminals of each individual fuse. In clamping thecircuit-wires to the terminals the insulating material is first cut awayfrom the end of the wire in such a manner as to form a shoulder whichwhen the wire is clamped will rest squarely against the end of theterminal, as shown in Fig. 2. It will then be seen that the bare portionof the wire or that from which the insulation has been removed isentirely inclosed by the terminal; but if the wire should be clamped insuch a way as to leave an uninsulated portion between the end of theterminal and the point where the insulation was cut away to form theshoulder the thickness ot' the wall oi the block through which the wirespass tothe terminal would efectually prevent any article from contactingwith the wire or wires from the outside and producing a short circuit.

It will thus be seen `from the construction herein shown that both thewires and terminals are so protected as to render accidentalshort-circuiting and shunting around the fuses between the terminalspractically impossible. The construction and arrangement are also Suchas to prevent persons coming in contact with the terminals, whichsometimes happens with dangerous results, particularly when thecircuitwires have become grounded.

The cover 2 of the block is intended to securely close the chambers 3,and in order to accomplish this the under side ot' the cover is providedwith downwardlyprojecting ears 19, which are designed to lit snugly inthe linger-recesses 16, formed in the sides of the block, and with acentral depending ear or lug 20, which tits into the linger-recess 17 ofthe partition 4. The lug 2O is provided with a screw-hole 21, whichopens into a circular recess 22 in the face of the cover ot' suiiicientdepth to entirely inclose the head of a screw 23, by which the'cover isfastened to the block. This screw passes through a hole 24 in the bottomof the block, which opens into a square recess 25, capable of receivinga nut 26, which receives the end of the screw. The partition 4 isprovided with circular recesses 27 of considerable depth, and from thebottoms o't' these recesses screw-holes 28 extend through the block.Screws are pressed through these holes into any suitable support towhich the block may be secured, and the recesses 27 will entirelyinclose the heads ot' the screws.

It sometimes happens that when a fuse is blown the inconvenienceoccasioned thereby is temporarily remedied by connecting the terminalswith a piece of fuse-wire. lith the uncovered blocks which are atpresent employed such an expedient frequently results in a lire byreason of' sparkingr or a l'lash from the blowing of the fuse-wire, andif the fuse-wire is not carefully secured to the terminals sparking isan almost inevitable result; but with a block constructed as hereinshown the temporary use of a fuse-wire could not possibly cause a fire,owing to the secure manner in which the terminals are inclosed, and,while my improved cut-out is designed to prevent the use of the commonfuse-wire as far as possible, should, however, it be employed thecut-out is so designed that the danger of ire is reduced to a minimum.

The fuse-block or cut-out herein described is thoroughly practical, andits construction by which the wires and terminals are protected obviatesshort-eircuiting and the danger of lire from the temporary use of'fuse-wire.

What I claim as new, and desire to secure by Letters Patent, is*

IOO

ISO

1. In a cut-out, a block having chambers separated by a partition, whichhas a central recess forming communication between the chambers 3similar recesses in the outer sides of the chambers, in line with therecess in the partition, and apertures through the ends of the chambers;a cover for said block having depending ears upon its under side, whichit into the recesses of the sides and partition of the block, a hole insaid cover which extends through the central ear, a corresponding holethrough the bottom of the block, forming a continuation of the aforesaidhole, and means for securing said block and cover together.

2. In a cut-out, a block having chambers which are separated by acentral partition, said chambers having apertures extending throughtheir ends, a recess in each side of the block communicating with achamber and a similar recess in the partition communicating with bothchambers, said recesses extending'from the top of the block to thebottom of the chambers; oppositely-arranged projections on the sides ofthe chambers, and adjacent to the recesses, which serve to contract thewidth of the chambers at that point, and holes through the partition forthe passage ofsecuring means.

3. In a cut-out, arblocl having chambers which are separated by acentral partition, the sides of said chambers and said partition beingformed centrally with recesses which extend from their top edges to thebottoms of the chambers; projections on the sides of said chambersadjacent to the recesses, which serve to contract the width of thechambers at this point; apertures through the ends of the chambers and acover for said block having projecting ears which iit into the recessesin the sides and partition of the block, and means for securing saidcover upon said block; in combination with terminals at the ends of saidchambers adjacent to and in alinement with the apertures the fusesconnecting said terminals, and the circuit-wires extending through saidapertures and secured to said terminals the extreme height of saidterminals, being less than the depth of the chambers.

4. In a cut-out, the combination of a block having chambers which arereduced in width for a part of their length at their central portionsand recesses in the sides of said chambers extending from the top of thesides to the bottom of the chambers; a thick wall at the ends of saidchambers having apertures therein which open into the chambers;terminals in the widened ends of said chambers adjacent to and on a linewith the apertures; the fuses connecting the terminals and which lie inthe narrow portion of the chambers, the said 'fuses and terminals lyingbelow the plane of the top of the block; the cover having depending earswhich fit into the recesses of the block, and means for securing saidcover upon said block.

In testimony whereof I aflix my signature in presence of two witnesses.

HARRY IV. LAWRENCE I/Vitnesses G. SARGENT ELLIOTT, CLARENCE R. DEDERICK.

